Auto merge of #22522 - ferjm:av.playback.improvements, r=Manishearth

HTMLMediaElement backoff protocol and other improvements to a/v playback

- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors

This PR implements a backoff protocol to keep us from dropping frames whenever it's possible. It also add some other improvements like:
- Clean up the implementation a little bit by adding all fetch request related state to `HTMLMediaElementFetchContext`.
- Make sure that we ignore responses from old requests.
- Set the stream to seekable iff there's support for range requests. This will likely change when we add the media cache.
- Implements part of [step 8 of the seek spec](https://html.spec.whatwg.org/multipage/media.html#dom-media-seek) where we bail out if the stream is not seekable.

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1 files changed, 3 insertions, 3 deletions

diff --git a/components/script/dom/bindings/trace.rs b/components/script/dom/bindings/trace.rs
index f94048c47de..e645fb181d5 100644
--- a/components/script/dom/bindings/trace.rs
+++ b/components/script/dom/bindings/trace.rs
@@ -38,7 +38,7 @@ use crate::dom::bindings::str::{DOMString, USVString};
 use crate::dom::bindings::utils::WindowProxyHandler;
 use crate::dom::document::PendingRestyle;
 use crate::dom::htmlimageelement::SourceSet;
-use crate::dom::htmlmediaelement::MediaFrameRenderer;
+use crate::dom::htmlmediaelement::{HTMLMediaElementFetchContext, MediaFrameRenderer};
 use crate::task::TaskBox;
 use app_units::Au;
 use canvas_traits::canvas::{
@@ -103,7 +103,6 @@ use servo_media::audio::panner_node::{DistanceModel, PanningModel};
 use servo_media::audio::param::ParamType;
 use servo_media::player::Player;
 use servo_media::Backend;
-use servo_media::Error as ServoMediaError;
 use servo_url::{ImmutableOrigin, MutableOrigin, ServoUrl};
 use smallvec::SmallVec;
 use std::cell::{Cell, RefCell, UnsafeCell};
@@ -484,11 +483,12 @@ unsafe_no_jsmanaged_fields!(AudioBuffer);
 unsafe_no_jsmanaged_fields!(AudioContext<Backend>);
 unsafe_no_jsmanaged_fields!(NodeId);
 unsafe_no_jsmanaged_fields!(AnalysisEngine, DistanceModel, PanningModel, ParamType);
-unsafe_no_jsmanaged_fields!(dyn Player<Error = ServoMediaError>);
+unsafe_no_jsmanaged_fields!(dyn Player);
 unsafe_no_jsmanaged_fields!(Mutex<MediaFrameRenderer>);
 unsafe_no_jsmanaged_fields!(RenderApiSender);
 unsafe_no_jsmanaged_fields!(ResourceFetchTiming);
 unsafe_no_jsmanaged_fields!(Timespec);
+unsafe_no_jsmanaged_fields!(HTMLMediaElementFetchContext);
 
 unsafe impl<'a> JSTraceable for &'a str {
     #[inline]